This relates generally to graphics processing and particularly to shadowing dynamic volumetric media.
Dynamic volumetric media are objects that have variable volumes, variable light transmittance, and self-shadowing. Self-shadowing is the effect of an object that creates shadows within itself. Examples of dynamic volumetric media include hair and translucent media such as smoke, dust, glass and fog.
Realistic lighting of dynamic volumetric media adds significant richness and realism to rendered scenes. The self-shadowing created by dynamic volumetric media provides important visual cues that define the shape and structure of that media. Computing self-shadowing in dynamic volumetric media involves accumulating partial occlusion between visual points and light sources in a scene. Accumulating partial occlusion involves capturing the effect of all of the volumetric objects between two points and is generally much more expensive in terms of computing cycles than computing shadows generated by opaque surfaces.